LED Driver IC Developed for High-Pixel-Count Animated Interior Lighting

­Melexis introduces the MLX81132, a programmable 24-channel MeLiBu® LED driver IC developed for high-pixel-count animated interior lighting. Combining high channel density, local processing, and 10BASE-T1S-Endpoint support, this new IC helps OEMs and Tier 1 suppliers to scale sophisticated RGB lighting. Furthermore, significantly reduces cost per pixel across applications including dashboards, doors, seats, center consoles, and roof lighting. 

Animated lighting is a key part of the modern vehicle experience, moving beyond decorative illumination to support personalization, brand identity, and more intuitive interaction between the vehicle and its occupants. As these concepts expand across the cabin, LED counts can quickly reach hundreds or even more than 1,000 light sources per vehicle, placing greater pressure on system cost, control architecture, processing requirements, and communication performance.

The MLX81132 tackles these challenges by concentrating the intelligence required to control multiple pixels within a single device. Its 24 constant-current LED channels, combined with 2x multiplexing, allow one IC to control up to 48 individual LEDs or 16 RGB pixels. In contrast, smart LED architectures integrate dedicated driver electronics into every RGB pixel. By sharing processing and driver functionality across multiple pixels, the MLX81132 reduces the amount of silicon required as LED counts increase, directly addressing one of the biggest barriers to deploying more sophisticated animated lighting: cost per pixel.

Designed around a 5 V supply, the device provides configurable LED currents up to 80 mA, with 16-bit PWM control supporting smooth color and intensity transitions. Channel bundling is also available where higher peak LED currents are required, extending the device across a wider range of interior lighting implementations.

Local Intelligence for Advanced RGB Lighting

At the heart of the MLX81132 is a programmable 16-bit microcontroller (MCU) with 64 KB Flash and 8 KB RAM, giving OEMs and Tier 1 suppliers the processing headroom to implement their own lighting functions directly within the LED driver. Pixel control, color calculations and other application functions can therefore be handled close to the LEDs, reducing the lighting-specific processing burden elsewhere in the vehicle.

Each connected LED can be individually controlled and diagnosed, including open-load, short-circuit and temperature monitoring. Calibration data can also be stored and processed locally, with individual LED temperature compensation helping maintain consistent color and intensity across the lighting system. This architecture also gives customers greater freedom to select RGB LEDs from different suppliers.

From Local Modules to Vehicle-Wide Lighting

As a MeLiBu 2.0 device, the MLX81132 supports adjustable data rates of up to 4 Mbit/s, providing the bandwidth required for responsive, highly dynamic animated lighting while allowing each IC to be individually addressed. Furthermore, unlike alternative smart LED architectures that rely on transmitting lighting information sequentially through every pixel, MeLiBu provides a bus-based communication approach suited to synchronized updates across distributed lighting nodes.

The same architecture gives designers greater freedom in how animated lighting is integrated into the vehicle. The MLX81132 can support compact local modules or broader vehicle-wide lighting systems, including increasingly centralized and zonal software-defined vehicle (SDV) architectures. Bus extension functionality also supports applications divided across multiple PCBs or lighting segments, allowing physically separated sections to operate as one coordinated lighting system.

The MLX81132 also includes a 12-bit differential ADC, SPI and I²C interfaces for connection to external devices, configurable fail-safe behavior, and integrated monitoring functions. Developed according to ISO 26262, it supports safety-related system implementations up to ASIL B and is suited for animated lightlines, contour lighting, dashboards, door panels, roof lighting, and emerging waterfall lighting concepts.

“Animated lighting is now a vehicle-wide interface, but increasing the number of pixels can quickly increase both system cost and architectural complexity,” said Michael Bender, Product Line Director at Melexis. “With the MLX81132, we are putting sophisticated LED control capability behind multiple pixels rather than replicating driver intelligence at every light point. This gives customers a highly flexible foundation for comprehensive interior lighting across the vehicle while significantly lowering the total bill of materials (BOM).”

The MLX81132 is the first member of a new generation of MeLiBu LED drivers. As a flash-programmable interior device, it gives customers full control over the software running on its integrated MCU. Additional code-free and exterior MeLiBu LED driver ICs will follow.

Samples of the MLX81132 are available now. For more information, please go here.